Expanding pulley



(No Model.)

J. E. DUSTIN. EXPANDING PULLBY.

No. 395,816. Patented Jan. 8, 1889.

[Ihm WIllllIlIlllllll/IIH Wzemes. 67% d, ty/g N. PETERS.Plmm-Lnhngmpher, washington, D. C.

trier are JOHN E. DUSTIN, OF LAVRENCE, MASSACHUSETTS.

EXPANDING PULLEY.

SPECIFICATION forming part of Letters Patent No. 395,816, dated January8, 1889.

August 16, 1888. Serial Not282,902.

To all w/zfo'nt t may concern:

Be it known that I, JoHN E. DUSTIN, a citizen of the United States,residing at Lawrence, in the county of Essex and State of Massachusetts,have invented certain new and useful Improvements in Expanding Pulleys;and l do hereby declare the following to be a full,

clear, and exact description ot' the invention, such as will enableothers skilled in the art to which it appertains to make and use thesame, reference being had to the accompanying drawings, and to lettersor iigures of reference marked thereon, which form a part of thisspecification.

This invention relates to expanding pulleys,7 so called, and has forits' object to provide a pulley which is composed of a series ofsectoral blocks arranged conccntrically with respect to each other, inorder to present a flat surface about which the belt is to travel.Furthermore, said sectoral blocks or belt-snp` porting portioii isadapted to converge or diverge in the respective acts ot' diminishing`or increasing the diameter ot the pulley and move radially in a plane atright angles to the shaft supporting said pulley. i

My invention, moreover, consists ot' actuating mechanism by which thesectoral blocks composing the belt-supporting portion of the expandingpulley are controlled and actuated, and said mechanism, in brief,consists of two apertured disks or spiders, so termed, located upon ashaft and operated. simultaneously in. opposite directions by aright-andlelt-screw-threaded rod. Suitably disposed upon the adjacentinner faces of the rims of said spiders is a series ot' rigidconvenging` bars so arranged that the two spiders may be caused toapproach er recede without said bars interferin or touchingl each other.Said bars intersect, however, at a point midway between said spiders.The belt-supporting portion or sectoral blocks are mounted onehalf oneach series of said converging' bars, and are interloclted in such amanner, hereinafter described, that they have no lateral movement, butare actuated radiallyT of the supportingshaft in a plane at right anglesto the longitudinal axis thereof.

Of the drawings accompanying this specification, Figure l represents avertical section (No model.)

longitudinally oi' the supporting-shaft with the pulley in elevation.Fig. 2 is an end view of one of the spiders, showing one-half thesectoral blocks and the converging operatingbars on which they aremounted. Fig. 3 is a vertical section longitudinally thereof. Fig. 4L isa central vertical section of one of the sectoral blocks. Figs. 5 and 6are opposite end views of said block and the curved plates whichinterlock the blocks. Fig. 7 is a developed sectional plan of severalot' the sectoral blocks and their intercoimecting plates, showing theirposition when the pulley is in an enlarged position.

Hitherto pulleys ot' the above-mentioned class have been composed of twotapering sections formed with alternating slots and extension-fingers,the slots of one section corresponding with and adapted to receive thetingers of the opposite cooperating section, in order that the twosections maybe telescoped or caused to approach or recede from eachother to vary the diameter ot the pulley. In this class of expandingpulleys the belt-supporting portion ot said pulleys is the point wherethe iingcrs of one section cross or intersect the lingers of theopposite section, and it is evident that the belt, in lieu of travelingupon a plane curved surface, is compelled to move in an obtuse V-shapedtrough, whereby it is bent and crippled and its durability greatlyimpaired.

The object ot' my invention is to provide an expanding pulley in which.a fiat belt-supporting portion is created, and at the same time toenable the diameter of said belt-supporting portion to be changed,enlarged, or reduced in diameter, as circumstances may require.

To carry out .my invention, as hereinbefore premised, l provide a hollowactuating-shaft, 2, suitably supported and longitudinally diametricallyslotted at 3 to permit endwise travel of two similar sleeve-nuts, et 4,which engage a rod, provided with right and left screw-threads. tubularshaft, and is actuated by 'a hand- This rod is interiorly of the wheel,G, or otherwise, as occasion may determine. The sleeve-nuts engage withtwin hubs 7 7, which iit exteriorly of the shaft 2, and

have longitudinal movement thereon caused neous opposite travel of saidhubs is thereby produced and the latter are caused to approach orrecede. Cast upon or otherwise rigidly attached to the adjacent ends ofsaid hubs are two apertured disks or spiders, S S', so called, whichform a portion of the expanding pulley and are moved toward and fromeach other with said hubs by the means above described. Each of saidspiders is provided with a series of bars, 9 9 9' 9', preferablyrectangular in cross-section. Said bars are circularly arranged upon therims of the spiders and are removably attached obl iquel y thereto, theends most remote from the spider converging toward a common center, asshown in Figs. 1 and The two series of converging bars are arranged tointersect midway between the apertured disks and alternate at equaldistances apart; hence when the spiders are caused to approach or recedethe said bars pass freely through and centrally of the spaces existingbetween the bars of the opposite co-operating spider. Thus in thepresent instance each spider is provided with eight bars, 9 9 9 9', andin order to create a circular belt-supporting portion with a flat faceupon which the belt shall rest l have provided one set ot' bars, 9 9,each wit-h a sectoral block, 10, the opposite bars, 9' 9', with sectoralblocks l0', all similar in shape and construction-that is, each block(see Fig. 4) is formed with an obliquely-disposed straight aperture, 12,aligned to coincide with the obliquity of the iixed bars 9 9 9' 9', uponwhich they are mounted. Beneath they are furnished with a hollow bossadapted to contain a spring, 13, which bears against the operating-bars9 9' to prevent rattling and render the pulley noiseless when inoperation. Said blocks are disposed concentrically at a point midwaybetween the spiders, or at the point of intersection between the oppositely-converging sets of bars 9 9 9' 9.

Transversely of the aperture 12, which receives the bars 9 9', andwithin the sectoral block, are formed two curved orifices, one, 14,adapted to receive a curved plate, 15, which is fastened securelytherein, the length of said plate being equal to the length ot' twoblocks, or thereabout. The adjacent orifice 16 is made much deeper, toenable the pulley to be expanded or contracted. Said orifices 14 16 arereversed in position on every alternate block. (See Fig. 7

To bind all the sectoral blocks together and compel them to move as aunit to maintain them concentric with each other, l have suppliedA eachsectoral block witlra curved plate, l5, above mentioned. Said platesalternate a line, a: fr, drawn centrally through the face of thebelt-supporting portion of the pulley, (See Fig. 3,) and are confined inthe orifice 14. The projecting end of said plate 15 engages in theorifice 16 in the next adjacent block, since each plate is about twicethe length of ablock. v Thus the blocks are made to converge or divergeby means of the play of the plates 15, vertically and longitudinally inthe orifices 16, nhile at the same time, by means of saidconnecting-plates 15, lat-eral divergence of the blocks is prevented andno eccentricity can occur. The ent-ire series of blocks are compelled tomove as a unit radially in or out, according to the size of pulleyrequired.

The operation of this expanding pulley is as follows: The shaft 2, whichserves to rotate the pulley mounted thereon, being' properly journalcd,rotation of the rod 5 will cause the spiders S S', by means of theirhubs and the actuating sleeve-nuts, which engage in the slots 3 S insaid shaft 2, to move in right lines along the latter either to approachor separate from each other. Presumin g the sectoral blocks are in a contracted position by causing the spiders to approach the blocks areforced obliquely along the bars upon which they are mounted, causingthem to diverge radially of the shaft 2. The belt-supporting surface isthereby increased in diameter and the pulley expanded. Then the pulleyis to be contracted, the spiders are caused to separate by reversemovement of the rod 5 and the blocks converge, always remaining in afixed position relatively to the shaft lengthwise. Yhen the pulley isfully contracted, the several sectoral blocks are contiguous and thecurved plates 15 are concealed.

It is evident that the curved plates may be cast integral with theblocks 10, in which case the slot 14 now shown would not be required.This is an obvious modification, the function of the curved plates 15remaining the same.

l. An expanding pulley consisting of a flat 'faced belt-supportingportion, a series of sectoral blocks circularly disposed, two apertureddisks or spiders oppositely movable in right lines, and thereversely-arranged converging series of bars secured to said disks, bywhich the sectoral blocks are caused to converge and divergeconcentrically as a unit, substantially as herein explained.

2. An expanding pulley composed of two apertured disks or spiderslmovable in right lines, two series of converging bars reversely disposedand intersecting midway of the spiders, the sectoral blocks apertured toreceive said bars, and the curved plates which connect said blocks tomaintain them concentric,

substantially as and Vfor purposes herein described.

3. In combination with a supporting-shaft and the circular hubs movablein right lines.

thereon, an expanding pulley, substantially as herein described,composed of the apertured disks or spiders, two reversely-arrangedconverging series of bars, the sectoral blocks operated by the latter,and the rotary rightand-left-serew-threaded rod, and the non-rotarysleeve-nuts movable endwise thereon, substantially as stated.

4. In combination with two oppositely IOO IIO

i y egaal@ s movable apertured disks or spiders and means, substantiallyas herein described, for actuating them in right lines, two series ofoppositely-converging bars rigidly affixed to said spiders intersecting'centrally between said disks, and the sectoral plates having theapertures 12, orifices 14 16, and the interconnecting' curved plates 15,all for purposes substantially herein explained.

5. In an expanding' pulley, a circular flat- 'aced belt-supportingportion composed of sectoral blocks 10 10', having a transverseaperture, 12, orifices 14 16, concentric with the face of the block, anda boss with a spring', 13, combined with two series ot'reversely-converging bars, 9 9 9 9', aiiixed upon circular apertureddisks or spiders oppositely movable to control the divergence orconvergence of said blocks, Substantially as herein stated.

G. In combination with two apertured disks or spiders, S 8', oppositelymovable in right lines, and the reversely-converging series of bars 9 99 9', the series of sectoral blocks 1() 10, formed with oriiices 14 1G,the positions of the latter being reversed in each alternate block, andthe intereonnecting` alternating plates 15, affixed in the orifice 14 inone block and movable vertically and lon gitndinally Within the orifice16 in the next adjacent block, all for purposes herein set forth anddescribed.

In testimony whereof I affix my signature in presence oi two wi tnesses.

JOI-IN E. DUSTIN.

IVtnesses:

H. E. Lone-E, W. H, ELLIS.

